Reel tension device



Feb. 21, 1950 cs. J. KENNEDY 2,498,336

REEL. TENSION DEVICE I Filed Jan. 25, 1946 2 Sheets-Sheet 1 IN V ENTOR ATTORN EY Feb. 21, 1950 G. J. KENNEDY REEL TENSION DEVICE 2 Sheets-Sheet 2 Filed Jan.- 25, 1946 lJlllj/ENTOR BY er 6111:4213! )kwm,

ATTORNEY Patented Feb. 21, 1950 REEL TENSION DEVICE 'Gilbert il'. Kennedy,i Philadelphia, Pa.,'assignor t0 Radio Corporation of America, a corporation of-Delaware Application January 25, 1946,Serial No. 643.289

6 Claims. :1 This invention relates to a new and useful-reel tension device which :is particularly adapted "to winding machines for "handling extraordinary thinzstrip material.

This application is a continuation in part'of my copending applicationiSerialNo. 536,219 filed May 18, 1944,"!10w abandoned.

An object of this invention .is *to provide a spring tension reel 01" -rdereeling device to .permit the winding .or-unwinding-of extra thinv strip material which .previously could .-not be handled because the tension applied /by .previously.known reel tension devices would cause the extra thin material to tear.

.Another object of 'thisinventionis to provide-a reel tension device which willlgreatlyreduce .the manufacturing cost of electrical condensers wound with alternately arranged strips of eX- traordinary thin metal foil and interposed insulating strip material.

.A feature of this invention is the arrangement of a spring frictioned mandrelrunning on conical pivot bearings for supporting a reel or spool having wound thereon a, roll of extra thinstrip material. An adjustable strip tension means 'is arranged at a distance from the mandrel axis to give minute frictional-adjustmentto the mandrel, such "that the roll of "thin strip material may be Wound or 'unreeled without any tendency to weaveor tear.

This reel tension device is particularly adapted to provide improved strip tension means for winding coil or roll condensers on a winding machine, as is described in the Harold'I. Danziger pate-nt,

1940547. According to my invention, the metal foil rollers are positioned on the winding machine, immediately over the winding feed rollers, tocontrol the weaving-of the foil. The dra -'or strip tension on the foil rolls, according 'to my invention, is made more sensitive to control and thus, permits the Winding of thinner foil than was heretofore practical in roll :condenser production.

My invention also conceives th "use of 'conical pivot bearings on a mandrel. The required pull on the foil reel (when the machine mentioned above starts Winding is ithe'reby cut down to almost nothing as the trictional resistance :of both the bearings and thespring friction is appliedso as to bear as close "to the center of the mandrel asisipra'ctical.

Roll condensers (which were previously wound on the-above mentioned Danz'iger machine) generally comprise :layers o'f paper and metal lioil wound inroll'form-s0 as to have the :long lengths 5,5

of paper and foil strips confined to a small space. These rolls were then impregnated "in oil and WaX,'&Ild placed in small -'sealed"'cans.

Prior to the adoption'of the metallic foil =d'ereeling method of myinvention, the above-men'- tioned capacity units were of necessity wound with a comparatively heavy'foil, for the reason that'it was found impossible'toemploy metal foil which was thinner than '.00025 (if an inchf because w'hen thinner foils wereuse'd, utter failure resulted due to the ram; that with "high speed winding necessary for high speed production methods, the thinner r011 would frequently break. "This breakage thus -caused a larger ;percentage of rejections and subsequent increase cost ofthe condensers. f

Each time the condenser fo'il breaks in'wind ing a'condenser, 'approxir'nately fi ftxo'f expensive paper and 3 ft. of expensive metallic foil i's scrapped, thus adding to the production'cost of the condensers. Opal -wax"impregnation was a'ls'o necessaryin order' to keep the electrica -capacity high and the physical "volume i small, in order :to place the' units in a small container. I

'Bymy invention, extremely thin .Efoil can now be used in "the production 0f condensers "without any danger of breakage. For example, I have found it possible to wind-capacitor units using aluminum foil or -other similar material as thin as .00'016 of aninch.

Because of using thethinnerifoil, it is possible to simplify the production I of roll condensers 'by employing 'a standard inexpensive castor oil timpregnati'on treatment.

In order to wind inexpensive iroll'condensers having a *maximum electrical capacity and a minimum physical volume, it :is :necessary that the standard oil type treatment mentioned above be employed, and 'inot ran "opal wax :treatment which reduces the physical size of a condenser.

'The standard castor .oil treatment "is inexpensive as compared with the opal waximetho'd.

My :invention will be understood by referring to the accompanying drawingiin' whichz Fig. '-1 is a front elevation "of a 'portion aof the Danziger winding machin (having mounted thereon two separate reel tension devices of :my invention,

Fig. 2 is a side elevation of Fig. '11,

Fig. 3 is an enlarged detailed section :of reel of my invention and Fig. 4iis :asideelevationof Fig. 3.

Referringinow in detail to Eigs. 1 and 2 of the drawing, the Danzigerimachine meritionediiabove as .Patent No. 11,940 ,847 nomprises a Kirame com! the 3 posed of two upstanding parallel plates, a front plate I and a rear plate II, spaced apart and suitably joined together by spacing members which include a motor support plate IOA. The main driving motor I2 is secured to plate IOA. Motor l2 has a pulley I4 which with a belt I5 drives a rotatable shaft I3 and a pulley I3A. The rotatable shaft I3 extends transversely through the frame at the lower portion thereof. One end of shaft I3 is split and projects forward from the front plate I0 and constitutes the winding mandrel for the condenser. The other end of the shaft I 3, in addition to pulley I3A, carries a gear I6 through a train of gears (not shown) which provides the proper movement for the shaft I3. Further description as to the structural details of the gear mechanism will be found by referring to the above mentioned patent, as the train of gears does not form a part of my present invention.

For reasons of clarity, all parts added to the Danziger winding machine which describe my invention are prefixed with a numeral 2, in order not to confuse my elements with those employed in the Danziger winding machine.

The front plate II] of the Danziger machine is shown with two pair of drums 23, 23' and 25, 25', each one of which is adapted to carry a roll of paper dielectric. Located intermediate the drums 23, 23' and 25, 25' are fixed shafts 24 and 24; which shafts in the Danziger machine, prior to my invention, were adapted to carry a roll of metal strip normally retained on the shaft by an ordinary spool. One of the reel tension devices of this invention is located on shaft or rod 24, and the other reel tension device is located on shaft or rod 24, each being located at an angle of about 45 with respect to the vertical axis of the machine, so that the strip of foil is brought down to guide rollers 21 and 21 located in a position closely adjacent the foil cut-01f knives 31. In this position, the foil rolls 221 and 221', which rolls are located so as to unwind on the dereeler device of this invention, are placed as close as possible in line with the paper strips, and thus,

results in keeping the weaving motion from the strip of foil as it unrolls at a minimum. The foil and paper dielectrics are brought closely together between rollers 28 and 28 and are wound into a condenser roll by rotatable shaft l3. When the two reel tension devices of this invention are employed on the Danziger machine, the foil sup- Port drums (shown as 24 and 24 only on the above mentioned patent) and their associated spring tensioned members are omitted.

The reel tension devices of this invention are substituted and mounted on shafts 24 and 24' of Fig. 1, and as mentioned above are adjusted in and out from the back of the machine by means of a threaded knurled handwheel 230 in order that the position of the foil will coincide exactly with the paper strips.

The reel tension device or dereeler 201 of this invention as shown in the drawings, comprises essentially a yoke member formed of a back plate 202 and a front plate 203. The back plate 202 has secured integral therewith a shaft bearing portion 202A which is reamed out to just clear shaft 24. The front plate 203 is provided with an integral handle portion 201. A rod 205 is secured to plate 202 by a set screw 206, and by having its ends pass through apertures in plates I0 and 20I rotation of the reel tension device is prevented. The handle portion and plate 203 have an enlarged aperture 201A, and a counter-.

bored portion 2013 is made sufiiciently large to seat an extension spring 233, the outside diameter of the spring being substantially the same as the outside diameter of the counterbored hole so that the spring will be retained centrally on member 201 and will not bear upon shaft 24. The front plate 203 is provided with large support rod apertures so that the machine operator can, by grasping the handle portion 201 and compressing the spring 233, rotate the front plate 203 by moving it forward toward the operator and thereby freeing it from the collar support rod 208 and also the guide rod 205. Then by turning the handle 201 approximately from the normal operating position, the front plate will be clear of the roll of foil 221, in which position the roll 221 may be withdrawn and a new roll of foil can be placed thereon. A set screw 202B retains collar support rod 208 in position after adjustment. A sloping collar 209 is secured to rod 208 by a set screw 2I0. The maximum width of collar 209 is located at the lower portion 21! and serves as a fulcrum point. A metal backing plate 221A keeps the spool of foil 221 in proper alignment. The hub portion 22I is secured in its operating position on mandrel 220 by means of a set screw 224. The lower end of the front and back plates are each provided with a mandrel bearing support, as is shown in detail by Figs. 3 and 4. The front plate 203 is shown as having a small aperture 2 I2 to retain a hardened steel conical pointed mandrel bearing center member 2l4. The back plate 202 has a larger aperture 2I3 which supports a cylindrical housing member 215. The forward part of the housing member is provided with a flange portion 2H5, and the rear portion has a smaller aperture in which there is provided a hardened steel mandrel conical bearing member 2l1. Intermediate the flange 2 I6 and the conical bearing member 2I1, the housing member 2I5 has an oil hole 2I8 for lubricating the mandrel and bearing 2I1. A set screw H9 is located near flange 2 I6, and is arranged with sufficient length to engage in a circular groove or annular slotted portion 220A in the mandrel 220, thereby preventing the mandrel from coming off from its bearing in the back plate 202 when the operator changes the foil rolls. The mandrel 220 is drilled and countersunk at each end thereof for turning on the ground conical center members 2M and 2l1. The reel 22| is provided with a hub portion 22IA which retains a roll of foil 221. The reel 22I also includes a flange roll backing portion 222 and a keyway 223. A flat steel spring 226 is located within the keyway 223. The spring 226 is secured to reel 22I by a roundhead machine screw 225. The purpose of spring 226 is to engage the inner cardboard wall of a spool, to retain the roll of thin aluminum foil 221 in a fixed position on the hub portion 22 IA. The forward end of shaft 24 is threaded at 23I with an adjustable threaded nut 232. Light friction is applied to the mandrel 220 by means of compressing the spring 233 which is placed around shaft 24 and arranged to bear only against member 201. The reel mandrel 220 rotates on the two hardened steel conical pivoted points 2 I 4 and 2 I1, as is shown in Fig. 3. As before mentioned, the collar 200 which is located on a rod 208 is chamfered away slightly to provide a fulcrum point 2I I. Very light pressure is exerted on the pivoted points by the spring 233 using point 2ll on collar 209 as the fulcrum point. The fulcrum point bears against the inside surface of plate 203. The spring tension device of this invention, as

mounted on shaft 24, is constrained from moving inwardby a collar 24!) which is secured to shaft 24 by a pin 2. A collar 248A locates member 202A in its proper forward position on shaft 24, and the collar is retained by a set screw 24 lA. A slight clearance is maintained between the spacing shaft 208 and the aperture in the plate 203, to prevent cramping or binding. Adjustment of the spring tension device, with respect to the front plate In of the Danziger machine, is made by the rotation of the threaded nut 232. This adjustment is required in order that the metal foil strips will unwind in proper alignment with the feed rollers 28 and 28'. The guide rod 205 is secured to the rear plate 202 by a set screw 2%. One end of guide rod 205 extends through a large aperture in plate Ill in front plate 203 and'positic-ns the reel tension device on plate H3. The accurate setting of the collar 209 is accomplished by the tightening of set screw 2 when the proper distance is determined (where the conical pivoted bearing 214 enters mandrel 220) for providing the proper friction on the mandrel by the adjustment of the tension of spring 233.

In the operation of the two reel tension devices of this invention, one device is placed in proper alignment on rod 24, and the other reel tension device is placed on rod 24'. The tension devices of this invention are placed in such a position on rods 24 and 24' that the lower or pivot ends of the two mandrels face each other and are set at a proper angle, preferably about 45 with respect to a line located in the center of the machine just above the feed rollers 28 and 28'. In this position, the spools of metal foil 227 and 222 are located so as to be in line with one side of each one of the guide posts 21 and 21. The foil strips are fed down to the winding mandrel l3 through the feed rollers 28 and 28, together with the paper strips arranged in their proper position with respect to the foils as shown in Fig. 1 of the drawing. In preparing the capacitors for winding, the operator adjusts the proper foil tension on the mandrel 220 by applying friction on bearings 2 Hi and 2 I! through the operation of turning the adjusting member 232 to compress spring 233. Adjustment of the fulcrum point 2 may also be made at this time. The paper and foil strips are next fed, through the feed rollers 28 and 28', to mandrel 13 which rotates until the desired number of turns are obtained. The foil strips are then cut off by the cut-off knives 31, as is customary with the usual method of winding condensers, and then the paper strips are cut off in the usual manner. The condenser is then removed from the machine, and a sticker is attached to the roll to prevent its unrolling, The foils and paper are then again brought down through the feed rollers to the winding mandrel I3, and the cycle of operation is repeated.

The reel tension device of this invention has proven to be very efficient for producing capacitors of extraordinary thin foil, and thus greatly reduced the cost of manufacture (for example by omitting the expensive wax process, by using less weight of metallic foil, by releasing other machines for production, and by an improved capacitor unit having a maximum capacity for a minimum volume).

It should be understood that this invention should not be limited to the winding of a particular type of capacitor mentioned in the specification but may be used to apply proper winding tension to any other thin strip or metal foil material.

What is claimed is:

IL A reel tension device for unwinding thin strip material from a reel comprising a pair of parallel spaced reel support members, a pivoted bearing located in each one of said support members at one end thereof, a reel for retaining a spool of thin strip material a mandrel for said reel secured for rotation between saidpivoted bearings, a member for spacing said parallel plates apart and to support said reel therebetween, said spacing member being located in apertures at the other end of each one of said support members, a support rod secured to a position intermediate the ends of said parallel support members, and a spring member secured to said support rod for applying friction between the pivoted bearings and said mandrel whereby a slight unwinding tension is maintained on the thin strip material.

2. A reel tension device for unwinding thin strip material from a reel comprising a pair of parallel spaced reel support members, a pivoted bearing located in each one of said supportmembers at one end thereof, a reel for retaining a spool of thin strip material, a mandrel for said reel secured for rotation between said pivoted bearings, an adjustable spacing member for spacing said parallel plates apart and to support said reel therebetween, said adjustable spacing member being located in apertures at the other end of each one of said support members, a support rod secured to a position intermediate the ends of said parallel support members, and an adjustable compression spring member secured to said support rod for applying friction between the pivoted bearings and said mandrel whereby a slight unwinding tension is maintained on the thin strip material.

3. A reel tensioned device for retaining a reel of thin strip material comprising a yoke member, an adjustable spacing member located at one end of said yoke member, a rotatable reel located within said yoke member and positioned at an end opposite from said adjustable spacing member, a collar having sloping sides secured to said adjustable spacing member and forming a fulcrum point on said yoke member, a rotatable mandrel for said reel, and a spring member secured to said yoke member for ap lying friction on said mandrel whereby a slight tension is maintained on the thin strip material when it is unwound.

4. The combination of a condenser winding machine of the type having a plate with shafts for supporting a plurality of spools, and a rotatable winding mandrel for winding a condenser from dielectric and thin metal strips located on said spools, a pair of reel tension devices for retaining the spools of thin metal strip, each one of said devices having a first reel support member which is adjustably secured to one of the shafts on said plate of the condenser winding machine, a second reel support member spaced from said first mentioned reel support member, an adjustable spacing member for spacing said first and second reel support members, a support rod for adjustably retaining said reel tension devices in an operative position, a reel for retaining a spool of thin metal strip, a mandrel for said reel secured for rotation between said first and second reel support members, and a spring compression member adjustably secured on said support rod for applying friction to said last mentioned mandrel, whereby a slight unwinding tenmachine of the type having a plate with shafts for supporting a plurality of spools, and a rotatable winding mandrel for winding a condenser from dielectric and thin metal strips located on said spools, a pair of reel tension devices for retaining the spools of thin metal strips, each one of said devices having a first reel support member which is adjustably secured to one of the shafts on said plate of said condenser winding machine, a second reel support member spaced from said first mentioned reel support and arranged to be removable therefrom, an adjustable spacing member for spacing said first and second reel support members, a support rod for adjustably retaining said reel tension devices in an operative position, a reel for retaining a spool of thin metal strip, a mandrel for said reel secured for rotation between said first and second reel support members, and a helical spring compression member adjustably secured on said support rod for applying friction to said last mentioned mandrel, whereby a slight unwinding tension is maintained on said thin metal strip.

6. The combination of a condenser winding machine of the type having a plate with shafts for supporting a plurality of spools, and a rotatable winding mandrel for winding a condenser from dielectric and thin metal strips located on said spools, a pair of reel tension devices for retaining is adjustably secured to one of the shafts on said plate of said condenser winding machine, a second reel support member spaced from said first mentioned reel support member and arranged to be removable therefrom, an adjustable spacing member for spacing said first and second reel support members, a support rod for adjustably retaining said reel tension device in an operative position, a reel for retaining a spool of strip material, a rotatable reel mandrel having an annular slotted portion for its retention on said first mentioned reel support member, to permit the replacement of a spool of thin strip material, and a spring compression member adjustably secured to said support rod for applying friction to said last mentioned mandrel, whereby a slight unwinding tension is maintained on said thin strip material.

GILBERT J. KENNEDY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 948,806 Ball Feb. 8, 1910 980,279 Ireland Jan. 3, 1911 1,196,740 Palmer Aug. 29, 1916 2,033,578 Kittel Mar. 10, 1936 2,149,631 Rodda Mar. 7, 1939 

